So Im sitting in the clean room here at work jacking around with stuff and theres this big expensive microscope. And one of the light filters on it is a small iris type mechanism similar to that of a camera shutter. And as I'm messing with it making it open and close and saying to my friend "look, its terminator", I began thinking. Why doesn't anyone make throttlebodies like this. You could have an infinitly variable opening. Say 6-8mm opening at idle, 35-45mm at half throttle and then a full 60mm at WOT, and not have anything [butterfly] blocking the inlet. It could also be variable so that it could optimize such things as WOT @ 3000 RPM not needing as much air as say WOT @ 7000 RPM. The mechanism would be very similar to a traditional TB, just replacing the butterfly with an iris mechanism.

 

Between manufacturing costs and quite a few more moving parts, I think I can see why they're not OEM fitment. The potential benefits do seem interesting...it'd be a neat research project to see if the added complexity is outweighed by performance or efficiency gains. It might be less obstructive at partial throttle openings than F1-style rotary spool throttles (line-bored to provide zero airflow restrictions at WOT), come to think of it... though airflow analysis would be needed to prove that.

Interesting idea...

 

interesting, but consider that the BMW valvotronic are not using TB at all, everything is controlled by the computer!

 

That type of mechanism can't handle pressure very well, and is meant to seal light, not gas or fluid, like a butterfly valve. It will deflect and jam.